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Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. VIII. An intensive HST, IUE, and ground-based study of NGC 5548

Korista, K. T. and Laor, A. (1995) Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. VIII. An intensive HST, IUE, and ground-based study of NGC 5548. Astrophysical Journal Supplement Series, 97 (2). pp. 285-330. ISSN 0067-0049. doi:10.1086/192144.

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We present the data and initial results from a combined Hubble Space Telescope (HST)/IUE/ground-based spectroscopic monitoring campaign on the Seyfert 1 galaxy NGC 5548 that was undertaken in order to address questions that require both higher temporal resolution and higher signal-to-noise ratios than were obtained in our previous multiwavelength monitoring of this galaxy in 1988-1989. IUE spectra were obtained once every 2 days for a period of 74 days beginning on 1993 March 14. During the last 39 days of this campaign, spectroscopic observations were also made with the HST Faint Object Spectrograph (FOS) on a daily basis. Ground-based observations, consisting of 165 optical spectra and 77 photometric observations (both CCD imaging and aperture photometry), are reported for the period 1992 October-1993 September, although many of the data are concentrated around the time of the satellite-based program. These data constitute a fifth year of intensive optical monitoring of this galaxy. In this contribution we describe the acquisition and reduction of all of the satellite and ground-based data obtained in this program. We describe in detail various photometric problems with the FOS and explain how we identified and corrected for various anomalies.

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Alternate Title:Steps toward determination of the size and structure of the broad-line region in active galatic nuclei. 8. An intensive HST, IUE, and ground-based study of NGC 5548
Additional Information:© 1995. The American Astronomical Society. Received 1994 September 8; Accepted 1994 September 28. We are deeply indebted to the entire FOS Instrument Team and Science Data Analysts, the HST scientists and engineers, and the Science Planning and Scheduling Branch for their patience and hard work. They share in the success of the HST portion of this project. K. T. K. spent valuable time with and especially wants to thank the following STScl staff members: Pierre Bely, Chris Blades, Howard Bushouse, John Fitch, Tony Keyes, Anne Kinney, Michael Rosa (ST /ECF), Peggy Stanley, Peter Stockman, Cindy Taylor, and Tom Wheeler. Extra special thanks go to Ralph Bohlin, who not only spent hours of his time in discussing the FOS flux calibration and related problems but also graciously made available the new FOS pipeline. At the Goddard Space Flight Center we gratefully acknowledge the work of Cathy Imhoff, Joy Nichols, and their staff, responsible for running the project's SWP spectra through the NEWSIPS pipeline, and for answering our many inquiries into the NEWSIPS calibration. We thank Richard Griffiths for kindly offering us the telescope pointing information from his parallel WFC observations. We also wish to acknowledge the support of several project coinvestigators who felt that their contribution did not warrant inclusion on the list of authors: B. Balick, T. J. Balonek, P. D. Barthel, R. D. Blandford, T. J.-L. Courvoisier, R. M. Cutri, G. J. Ferland, P. M. Gondhalekar, D. Kazanas, C. F. McKee, E. J. A. Meurs, E. Perez, A. Robinson, E. Rokaki, J. L. Sanz, T. Storchi-Bergmann, E. van Groningen, M. J. Ward, C.-C. Wu, and W. Zheng. Finally, we thank R. Giacconi, H. S. Stockman, and R. E. Williams (STScl), Y. Kondo (/UE-GSFC), and the directors of the various ground-based observatories used in this program for their support of this demanding program. We are pleased to acknowledge financial support of the spacebased component of this project by NASA through grants NAG5-1824 and STScl grant G0-3484.0l-91A. We also acknowledge support for the ground-based observations through several agencies, including the following: National Science Foundation, grants AST-9112870 (Ohio State University), AST-8957063 (University of California, Berkeley); NASA Long-Term Space Astrophysics grants NAGW-2678 (K. H.) and NAGW-3315 (B. M. P.); BMFT grant Verbundforschung Astronomie DFG Ko 857/13-1 (Universitiits-Stemwarte Gottingen), ESO C&EE Program for grant A-01-057 (Crimean Astrophysical Observatory); and Russian Basic Science Foundation grant 94-02-04885a(N. G. B. and A. I. S.).
Funding AgencyGrant Number
BMFTDFG KO 857 / 13-1
ESO C&EE ProgramA-01-057
Russian Basic Science Foundation94-02-04885a
Subject Keywords:galaxies: active - galaxies: individual (NGC 5548) - galaxies: nuclei galaxies: photometry - galaxies: Seyfert - ultraviolet: galaxies
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Deposited On:12 Aug 2014 21:24
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